This invention relates to the field of electrical switches, and more specifically to an arc chute for a switch.
Electrical switches such as circuit breakers and transfer switches typically include arc chutes located proximate the contacts of the switch to extinguish the arc that is produced when the switch is tripped and the contacts of the switch are rapidly opened. An arc chute typically includes a series of metallic plates that are configured in a spaced apart relationship and held in place by dielectric side panels. When the contacts of the switch are opened, the resulting arc is driven to the metallic plates of the arc chute where the arc is then extinguished by the plates. Typically, the metallic plates are held in place by tabs on the plates which extend through holes in the side panels so that the tabs can be either staked in place or fastened by external fasteners. Such an assembly process is time consuming and the resulting arc chute structure can be bulky requiring a relatively large mounting area within the switch.
The present invention provides an arc chute having features to allow for easy manufacture and assembly of the arc chute and allow for an improved switch incorporating the arc chute. In one aspect, an arc chute includes a first side wall having a plurality of holes, a second side wall having a plurality of holes and spaced apart from the first side wall, and a plurality of arc chute plates mounted between the first and second side walls. Each of the plurality of arc chute plates include one or more laterally extending tabs extending from the sides of each plate. Each of the laterally extending tabs are shaped to be interference fitted within one of the plurality of holes. Each of the laterally extending tabs are dimensioned to not substantially extend beyond an outer surface of each of the side walls.
Another aspect includes a method of manufacturing an arc chute. In one embodiment, a method for assembling an arc chute includes interference fitting one or more tabs on a first side of an arc chute plate into a hole on a first arc chute side wall, and interference fitting one or more tabs on a second side of the arc chute plate into a hole on a second arc chute side wall.
Another aspect provides a switch. In one embodiment, a switch includes a case having an arc chute mounting area having a ridge near a back portion of the arc chute mounting area. An arc chute is mounted within the arc chute mounting area. The arc chute includes a pair of side walls and a plurality of arc chute plates mounted between the pair of side walls, wherein each of the pair of side walls includes a movable tab which is removably engageable with the ridge.
Among other advantages, one or more embodiments of the present system provide an arc chute which is easily manufactured, has a relatively small design, and is easily removable from a switch.